1. Field
Methods and apparatuses consistent with exemplary embodiments relate to manufacturing a circuit board including a cavity and a chip package, and a circuit board manufactured by using the method.
2. Description of the Related Art
As sizes of components of electronic devices have recently reduced and consumers prefer one product with various functions, the number of components of an electronic device has increased. Accordingly, there is a demand for technology for mounting many electronic components on a circuit board at a high density.
A multi-layer circuit board is an element of an electronic device which is formed by stacking a plurality of substrates as multi-layers in each of which electronic components are mounted. Since a multi-layer circuit board may perform more electrically complex functions than a single-sided board or a double-sided board, and may enable electronic components to be mounted thereon at a high density, the multi-layer circuit board is widely applied to a variety of electronic devices.
In particular, there is a recent demand for a system integration technology for making an electronic product light, thin, short, and small, and a technology of manufacturing a cavity printed circuit board (PCB) has attracted attention as a system integration technology. In a cavity PCB, since components are, instead of being completely embedded on a PCB, embedded in a cavity that is formed in a direction in which a chip is mounted, it is much more efficient in the cavity PCB to replace the components or check the components than in an embedded PCB.
However, a multi-layer technology is rarely applied to a cavity PCB. This is because it is difficult to accurately form a cavity and an internal circuit in the cavity may be damaged during plating or etching performed in a PCB process.
In particular, in a method of selectively forming a cavity by using laser drilling in a PCB on which finished components are stacked, since it is difficult to adjust a depth, an internal circuit pattern and an internal insulating layer may be frequently damaged. Also, when a cavity is formed by using a router, since there is a big difference in processing precision and the cavity has to be formed individually, product reliability during mass production may be reduced and it is difficult to mass produce devices due to low productivity. Also, a method of selectivity forming a cavity by precisely punching a position of the cavity in a finished product by using a punching device inevitably results in damage to an outer wall of the cavity. Due to the damage to the outer wall of the cavity, de-lamination due to moisture absorption and damage to a bottom surface of the cavity are caused. Due to costs of manufacturing the punching jig, overall manufacturing costs are increased and a design width of the cavity is very small. When a cavity is formed and components are stacked before an insulating layer is stacked, since it is difficult to control the flow of a thermosetting resin, smears tend to be produced and an additional desmear process has to be performed. Also, since it is difficult to completely remove smears, the reliability of a substrate is reduced and mass productivity is reduced.